This invention relates to a data processing system capable of running at least under a data input mode, and more particularly to a system wherein the data input mode can be interrupted to be changed to other data processing modes such as a delete mode, a print mode and so on as required, and restored the input mode as being before interrupted when returned to the input mode.
A data processing system generally runs under a plurality of data processing modes including a word processor mode for preparing and/or editing data files within a text memory, a print mode for printing a content of a selected data file stored in the text memory, and a list mode for displaying a list of data files stored in the text memory as well as for deleting a selected data file from the text memory. These modes are indicated on a display screen in the form of menu so as to allow an operator to select a desired mode with a cursor.
In such data processing systems, it has been necessary to leave the currently selected mode in order to change the proceesing mode, which requires a series of bothersome operations.
In view of the above, there has been proposed such data processing devices as being designed to be changable the processing modes without the operations to leave the currently selected mode. In other words, with these data processing systems, mere operation for chaning the processing mode causes automatic leaving from the currently processed mode and entry into the newly selected mode.
With the above constructed systems, however, as the current mode is terminated upon change of the mode, the processing being executed at the time of mode-change under the currently selected mode is automatically cancelled. Accordingly, it becomes necessary to re-entry several data and take some preparatory operations so as to resume the above processing when the currently selected mode is re-selected after the required processings under the newly selected mode finished.